Remedios para un cuerpo político que declina. El arbitrismo de Manuel Gaytán de Torres y el estrechamiento de los vínculos transatlánticos de la monarquía hispánica (siglo XVII); Remedies for a Body Politic in Decline. Manuel Gaytánde Torres’ Arbitrism and the Strengthening of TransatlanticTies in the Spanish Monarchy (17th century) Amadori, Arrigo Este artículo analiza los memoriales del jerezano Manuel Gaytán de Torres, quien elaboró un arbitrismo de gran envergadura, heterogeneidad y originalidad de síntesis que articula problemáticas y espacios geográficos diversos en una propuesta funcional del mundo ibérico. Su obra permite contemplar la construcción intelectual de la monarquía policéntrica desde la óptica de un arbitrismo en el que los virreinatos americanos se relacionan de forma sistémica con el mundo europeo, reproduciendo las percepciones contemporáneas acerca de las dificultades y de las soluciones para los disfuncionamientos de las posesiones de los Austrias.; This article analyses the memorials of Manuel Gaytán de Torres, a native of Jerezwho developed an arbitrism of great scope, heterogeneity and originality of synthesis thatarticulates various issues and geographic spaces into a functional proposition of the Iberianworld. His work facilitates an understanding of the intellectual construction of the polycen-tric monarchy from the perspective of an arbitrism in which the American viceroyalties aresystematically related to the European world, and reproduces contemporary perceptions ofthe difficulties posed by the different dysfunctions of the Austrian possessions and their solu-tions.

Equidad y politicas universitarias: perspectivas desde latinoamerica Yuni, Jose Alberto; Melendez, Cecilia Evangelina; Diaz, Ana Griselda En este artículo nos proponemos abordar algunas cuestiones de la equidad en la Educación Superior, desde la singular perspectiva de la realidad latinoamericana. Nuestro interés radica en dar cuenta de los modos y posiciones teóricas a través de las cuales se definen políticas de equidad en el campo de la Educación Superior y se establecen sentidos y significados sociales en torno a ellas. En la primera parte se realiza una breve caracterización de los escenarios de la Educación Superior en Latinoamérica, tanto en lo que se refiere a los procesos socio-políticos de carácter estructural, como a la dinámica de los sistemas de Educación Superior. En la segunda parte, se efectúa una reconstrucción conceptual que nos permita mostrar los desplazamientos operados en las políticas universitarias de las últimas décadas y que han desembocado en la implementación de las llamadas políticas de equidad. En la tercera parte del artículo, se analizan diferentes niveles de especificación del concepto de equidad en las dinámicas universitarias, las que dan cuenta de su potencial productivo de prácticas. Finalmente, se describen algunas de las iniciativas más importantes desplegadas en los últimos años por algunos países de la región, enmarcadas en políticas de equidad, señalando sus efectos y alcances.

Consumo Compensatorio: ¿Una nueva forma de construir sensibilidades desde el Estado? de Sena, Angélica; Scribano, Adrián Oscar La motivación central del presente trabajo es explorar la emergencia de un fenómeno social que, al menos, se viene consolidando en los últimos catorce años en Latinoamérica en general y en Argentina en particular: el consumo compensatorio. El artículo sintetiza un conjunto de indagaciones que venimos realizando en el cruce entre una sociología de las políticas sociales y una manera de entender la sociología de los cuerpos/emociones. La estrategia argumentativa que hemos seleccionado es la siguiente: a) se bosqueja el punto de partida conceptual sobre los cruces entre políticas sociales y sensibilidades, b) se presenta un esquema de las conexiones consumo y disfrute en la actualidad, c) se muestran algunos resultados de las indagaciones que se han utilizado como base del análisis y d) se conceptualiza de modo sintético una noción de consumo compensatorio como resultado de la argumentación. Se finaliza proponiendo la posibilidad de que el consumo compensatorio es hoy, tal vez, “una política social” retomada desde y para el mercado.; The main motivation of this paper is to explore the emergence of a social phenomenon that, at least, has been con-solidating in the last fourteen years in Latin America in general and Argentina in particular, the compensatory con-sumption. The article summarizes a number of inquiries we have done in the cross between a sociology of socialpolicies and a way to understand the sociology of the body / emotions. The argumentative strategy we have chosenis the following: a) we stand the conceptual starting point on crossings between social policies and sensitivities, b)we outline a pattern of consumption and enjoyment connections at present, c) we shown the results of some inquirieswhich has been used as the basis of analysis and d) we conceptualize synthetically a notion of compensatory con-sumption as a result of this argument. Our essay concludes by proposing the possibility that compensatory con-sumption is today perhaps, the "social policy" taken up from and to the market.

Argentina Tercer Mundo: Nueva izquierda, emociones y política revolucionaria en las décadas de 1960 y 1970 Manzano, Adriana Valeria This article analyzes the emergence and spread of an assimilation of Argentina with the Third World. It contends that “thirdworldism” was a key component of the ideas and practices of Argentina’s New Left. The political and cultural actors that coalesced into that New Left focused on the contrasts between “modernizing” spaces and phenomena, and the grievous living and working conditions in the provinces of the Northeast and the Northwest. These latter helped question the modernizing narratives at the same time that they contributed to approach Argentina to the usual images of the “geography of rebellion” of the Third World. The focus on the contrasts also allowed for the shaping of a collective emotion, indignation, which in turn heightened ideological beliefs and politico-cultural practices. The first segment explores the making of the parameters of “indignation” in its linkages with the emphasis on social, geographical, and economic contrasts. The second segment reconstructs the travel practices and cultural consumptions of a cohort of young people who experienced their political socialization in the intersection of the 1960s and 1970s. Many of the youths involved in those initiatives believed that Peronism represented the best way to a national and social “liberation” that they thought was impending. The last segment analyzes the juncture of 1973 as a “Thirdworliest spring”.; Este artículo analiza la emergencia y expansión de una asimilación de la Argentina con el Tercer Mundo. Sostiene que el tercermundismo fue un componente clave de las ideas y las prácticas de la Nueva Izquierda. Los actores políticos y culturales que convergieron en esa Nueva Izquierda focalizaron en los contrastes entre los espacios y fenómenos “modernizadores” y las condiciones de vida y trabajo en las provincias del noreste y del noroeste. Estas últimas permitían poner en entredicho las narrativas de modernización, a la vez que acercaban a la Argentina a las imágenes paradigmáticas de la “geografía de la rebelión” tercermundista. El foco puesto en los contrastes abonaba la configuración de una emoción colectiva, la indignación, que a su vez potenciaba creencias ideológicas y prácticas político-culturales. El primer segmento analiza cómo se delinearon los parámetros de la indignación en consonancia con el énfasis en los contrastes sociales, geográficos y económicos. El segundo segmento reconstruye prácticas de viajes y consumos culturales de jóvenes en su proceso de socialización política en la intersección de las décadas de 1960 y 1970. Muchos de quienes participaron de esos emprendimientos encontraron en el peronismo una vía para una “liberación” nacional y social que veían en marcha. En el último segmento el artículo se detiene a analizar la “primavera” tercermundista de 1973.

NF-κB transcriptional activity is modulated by FK506-binding proteins FKBP51 and FKBP52: a role for peptidyl-prolyl isomerase activity Erlejman, Alejandra Giselle; de Leo, Sonia Alejandra; Mazaira, Gisela Ileana; Molinari, Alejandro Martín; Camisay, Maria Fernanda; Fontana, Vanina Andrea; Cox, Mark; Piwien Pilipuk, Graciela; Galigniana, Mario Daniel Hsp90 binding immunophilins FKBP51 and FKBP52 modulate steroid receptor trafficking and hormone-dependent biological responses. With the purpose to expand this model to other nuclear factors that are also subject to nuclear-cytoplasmic shuttling, we analyzed whether these immunophilins modulate NF-κB signaling. It is demonstrated that FKBP51 impairs both the nuclear translocation rate of NF-κB and its transcriptional activity. The inhibitory action of FKBP51 requires neither the peptidylprolyl-isomerase activity of the immunophilin nor its association with Hsp90. The TPR domain of FKBP51 is essential. On the other hand, FKBP52 favors the nuclear retention time of RelA, its association to a DNA consensus binding sequence, and NF-κB transcriptional activity, the latter effect being strongly dependent on the peptidylprolyl-isomerase activity and also on the TPR domain of FKBP52, but its interaction with Hsp90 is not required. In unstimulated cells, FKBP51 forms endogenous complexes with cytoplasmic RelA. Upon cell stimulation with phorbol ester, the NF-κB soluble complex exchanges FKBP51 for FKBP52, and the NF-κB biological effect is triggered. Importantly, FKBP52 is functionally recruited to the promoter region of NF-κB target genes, whereas FKBP51 is released. Competition assays demonstrated that both immunophilins antagonize one another, and binding assays with purified proteins suggest that the association of RelA and immunophilins could be direct. These observations suggest that the biological action of NF-κB in different cell types could be positively regulated by a high FKBP52/FKBP51 expression ratio by favoring NF-κB nuclear retention, recruitment to the promoter regions of target genes, and transcriptional activity.

Identification of Candidate Genes Associated with Leaf Senescence in Cultivated Sunflower (Helianthus annuus L.) Moschen, Sebastián Nicolás; Bengoa Luoni, Sofia Ailin; Paniego, Norma Beatriz; Hopp, Horacio Esteban; Dosio, Guillermo Aníbal Adrián; Fernández, Paula del Carmen; Heinz, Ruth Amelia Cultivated sunflower (Helianthus annuus L.), an important source of edible vegetable oil, shows rapid onset of senescence, which limits production by reducing photosynthetic capacity under specific growing conditions. Carbon for grain filling depends strongly on light interception by green leaf area, which diminishes during grain filling due to leaf senescence. Transcription factors (TFs) regulate the progression of leaf senescence in plants and have been well explored in model systems, but information for many agronomic crops remains limited. Here, we characterize the expression profiles of a set of putative senescence associated genes (SAGs) identified by a candidate gene approach and sunflower microarray expression studies. We examined a time course of sunflower leaves undergoing natural senescence and used quantitative PCR (qPCR) to measure the expression of 11 candidate genes representing the NAC, WRKY, MYB and NF-Y TF families. In addition, we measured physiological parameters such as chlorophyll, total soluble sugars and nitrogen content. The expression of Ha-NAC01, Ha-NAC03, Ha-NAC04, Ha-NAC05 and Ha-MYB01 TFs increased before the remobilization rate increased and therefore, before the appearance of the first physiological symptoms of senescence, whereas Ha-NAC02 expression decreased. In addition, we also examined the trifurcate feed-forward pathway (involving ORE1, miR164, and ETHYLENE INSENSITIVE 2) previously reported for Arabidopsis. We measured transcription of Ha-NAC01 (the sunflower homolog of ORE1) and Ha-EIN2, along with the levels of miR164, in two leaves from different stem positions, and identified differences in transcription between basal and upper leaves. Interestingly, Ha-NAC01 and Ha-EIN2 transcription profiles showed an earlier up-regulation in upper leaves of plants close to maturity, compared with basal leaves of plants at pre-anthesis stages. These results suggest that the H. annuus TFs characterized in this work could play important roles as potential triggers of leaf senescence and thus can be considered putative candidate genes for senescence in sunflower.

Are Local Filters Blind to Provenance? Ant Seed Predation Suppresses Exotic Plants More than Natives Pearson, Dean E.; Icasatti, Nadia Soledad; Hierro, Jose Luis; Bird, Benjamin B. The question of whether species’ origins influence invasion outcomes has been a point of substantial debate in invasion ecology. Theoretically, colonization outcomes can be predicted based on how species’ traits interact with community filters, a process presumably blind to species’ origins. Yet, exotic plant introductions commonly result in monospecific plant densities not commonly seen in native assemblages, suggesting that exotic species may respond to community filters differently than natives. Here, we tested whether exotic and native species differed in their responses to a local community filter by examining how ant seed predation affected recruitment of eighteen native and exotic plant species in central Argentina. Ant seed predation proved to be an important local filter that strongly suppressed plant recruitment, but ants suppressed exotic recruitment far more than natives (89% of exotic species vs. 22% of natives). Seed size predicted ant impacts on recruitment independent of origins, with ant preference for smaller seeds resulting in smaller seeded plant species being heavily suppressed. The disproportionate effects of provenance arose because exotics had generally smaller seeds than natives. Exotics also exhibited greater emergence and earlier peak emergence than natives in the absence of ants. However, when ants had access to seeds, these potential advantages of exotics were negated due to the filtering bias against exotics. The differences in traits we observed between exotics and natives suggest that higher-order introduction filters or regional processes preselected for certain exotic traits that then interacted with the local seed predation filter. Our results suggest that the interactions between local filters and species traits can predict invasion outcomes, but understanding the role of provenance will require quantifying filtering processes at multiple hierarchical scales and evaluating interactions between filters.

Efficacy of albendazole in combination with thymol against Echinococcus multilocularis protoscoleces and metacestodes Albani, Clara Maria; Elissondo, María Celina The larval (metacestode) stage of the tapeworm Echinococcus multilocularis causes alveolar echinococcosis (AE), a mainly hepatic disease characterized by continuous asexual proliferation of metacestodes by exogenous budding, resulting in the tumor-like, infiltrative growth of the parasite lesion. Current chemotherapeutical treatment of AE relies on the use of benzimidazoles, albendazole (ABZ) and mebendazole, but these drugs act parasitostatic rather than parasitocidal, and due to their low success rate they imply a lifelong application causing severe side effects. Thymol is one of the major components of the essential oils of Thymus and is a widely known anti-microbial agent. The aim of the present work was to compare the efficacy of albendazole (ABZ) and thymol separately or combined on E. multilocularis protoscoleces and metacestodes. For this purpose, microscopical examinations at different time points were carried out. Moreover the tegumentary enzyme gamma glutamyl transferase (GGT) was measured to quantify the damage in metacestodes. Even though treatments of in vitro cultured E. multilocularis protoscoleces or metacestodes with ABZ or/and thymol showed that the drugs have an adverse effect on parasite viability, the combination of the two compounds at the concentration of 10 μg/ml showed the maximum anti-parasitic effect. Three days postincubation the first effects of the treatment were detected on protoscoleces and a marked reduction in viability (33%) was registered at day 18. Incubation of E. multilocularis metacestodes in the presence of ABZ 10 μg/ml + thymol 10 μg/ml during 10 days resulted in dramatic alterations such as strongly irregular and fissured surface and markedly disrupted vesicles. Scanning electron microscopy showed that protoscoleces as well as the germinal layer of E. multilocularis metacestodes were dramatically damaged following ABZ or/and thymol treatment. Also an important increase of tegumentary enzyme GGT was registered after 72 h postincubation with both drugs. The data reported in this article demonstrate a clear in vitro effect of ABZ + thymol against E. multilocularis protoscoleces and metacestodes.

First detection of hepatitis E virus in Central Argentina: Environmental and serological survey Martinez Wassaf, Maribel Graciela; Pisano, María Belén; Barril, Patricia Angelica; Elbarcha, Osvaldo C.; Pinto, Marcelo A.; Oliveira, Jaqueline Mendes de; DiGiusto, Pablo; Nates, Silvia Viviana; Ré, Viviana Elizabeth Background: The hepatitis E virus (HEV) is an emergent causative agent of acute hepatitis worldwide, transmitted by fecal-oral route. In Argentina it is considered rare, so differential laboratory testing is not routinely performed. Besides, in Argentina's central area epidemiological and molecular characteristics of HEV are still unknown. Objectives: Provide evidence of local circulation of HEV by molecular detection on environmental samples and by serological survey in healthy adult population of Córdoba city, Argentina. Study design: Environmental surveillance was conducted in river and sewage samples collected between 2007 and 2009–2011. Viral detection was performed by RT-Nested PCR of ORF-1 and ORF-2 partial regions. Anti-HEV IgG was determined by EIA in 433 serum samples collected between 2009 and 2010. Results: HEV was detected in 6.3% of raw sewage samples and in 3.2% of riverine samples. Nucleotide sequencing analyses revealed that all isolates belonged to genotype 3, subtypes a, b and c. The prevalence of IgG anti-HEV was 4.4%. Seroprevalence increased with the age of the individuals (OR: 3.50; 95% CI 1.39–8.87; p = 0.0065) and, although the prevalence was higher in low income population, no statistical relation was found between anti-HEV and socioeconomic level. Conclusions: The environmental findings added to serological results, demonstrate that HEV circulates in central Argentina. Contamination of water with HEV could represent a route of transmission for local populations, which have a high number of susceptible individuals. This fact alerts local health care systems in order to include detection of HEV in the diagnostic algorithm of viral hepatitis.

Increment of the collective pinning energy in Na1 − xCa x Fe2As2 single crystals with random point defects introduced by proton irradiation Haberkorn, Nestor Fabian; Kim, Jeehoon; Maiorov, B.; Usov, I.; Chen, G. F.; Yu, W.; Civale, L. We study the influence of random point defects introduced by 3 MeV proton irradiation (doses 1 × 1016 and 2 × 1016 cm2) on the vortex dynamics of Na x Ca1 − xFe2As2 (x = 0.5 and x = 0.75) single crystals. Our results indicate that the irradiation produces an enhancement of the critical current density and a reduction of the creep rate in vortex relaxation. The plateau in the temperature dependence of vortex creep rate initially present in as-grown single crystals disappears after irradiation. This fact can be associated with a large increment of the collective pinning energy (from <100 to 350–400 K). On the other hand, Maley analysis indicates that after irradiation both samples present a glassy exponent μ close to the one expected in the so-called large bundle regime (μ ≈ 7/9) for random point defects.

Memory beyond expression Delorenzi, Alejandro; Maza, Francisco Javier; Suárez, Luis Daniel; Barreiro, Karina Andrea; Molina, Víctor Alejandro; Stehberg. J. The idea that memories are not invariable after the consolidation process has led to new perspectives about several mnemonic processes. In this framework, we review our studies on the modulation of memory expression during reconsolidation. We propose that during both memory consolidation and reconsolidation, neuromodulators can determine the probability of the memory trace to guide behavior, i.e. they can either increase or decrease its behavioral expressibility without affecting the potential of persistent memories to be activated and become labile. Our hypothesis is based on the findings that positive modulation of memory expression during reconsolidation occurs even if memories are behaviorally unexpressed. This review discusses the original approach taken in the studies of the crab Neohelice (Chasmagnathus) granulata, which was then successfully applied to test the hypothesis in rodent fear memory. Data presented offers a new way of thinking about both weak trainings and experimental amnesia: memory retrieval can be dissociated from memory expression. Furthermore, the strategy presented here allowed us to show in human declarative memory that the periods in which long-term memory can be activated and become labile during reconsolidation exceeds the periods in which that memory is expressed, providing direct evidence that conscious access to memory is not needed for reconsolidation. Specific controls based on the constraints of reminders to trigger reconsolidation allow us to distinguish between obliterated and unexpressed but activated long-term memories after amnesic treatments, weak trainings and forgetting. In the hypothesis discussed, memory expressibility – the outcome of experience-dependent changes in the potential to behave – is considered as a flexible and modulable attribute of long-term memories. Expression seems to be just one of the possible fates of re-activated memories.

Experimental in vitro infection of rat osteoblasts with measles virus stimulates osteogenic differentiation Ayala Peña, Victoria Belen; Santillán, Graciela Edith; Scolaro, Luis Alberto In this work we characterized the infection of a primary culture of rat osteoblastic lineage cells (OBCs) with measles virus (MeV) and the effect of infection on cell differentiation and maturation. Infection of OBCs with MeV led to high titers of infectivity released early after infection. Also, analysis of mRNAs corresponding to osteogenic differentiation markers like alkaline phosphatase (ALP), bone sialo-protein (BSP) and bone morphogenetic proteins (BMPs) 1-4-5-7 in OBCs revealed higher values (2–75-fold of increment) for infected cells in comparison with uninfected controls. Differentiation of OBCs in osteogenic medium prior to infection influenced the level of stimulation induced by MeV. Furthermore, treatment of OBCs with Ly294002, a PI3K/AKT inhibitor, increased viral titers, whereas treatment with 10 μM or 100 μM ATPγS diminished MeV multiplication. In addition, increments of osteogenic differentiation markers induced by MeV infection were not modified either by treatment with Ly294002 or ATPγS. These data provide the first evidence demonstrating that MeV can infect osteoblasts in vitro leading to osteoblastic differentiation, a key feature in bone pathogenic processes like otosclerosis.

Satisfaction, professional mobility and leadership in academic-scientific organisations Aparicio, Miriam Teresita The research work has been done in the field of social and organizational psychology. It is aim to analyze the factors which influence the levels of satisfaction and achievement reached by those working for scientific organizations and their relationship with professional mobility (Andrews, Aichholzer, Cole, Mittermeir, Stole-Heiskanen, UNESCO—United Nations Educational, Scientific and Cultural Organization, 1971) [1]. A stratified sample was taken from universities and different disciplines, based on a population of teachers from the Cuyo region (N = 355 R + D—Research & Development Units) (5% error margin). At this first stage, the research teachers were from Universidad Nacional de Cuyo (N = 53 Research Units): one chief or director and members. Quantitative techniques were used (two questionnaires). The results show that researchers’ satisfaction at different levels is connected with professional mobility and disciplinary fields. Regarding leadership, and considering professional mobility, a general feeling of satisfaction emerges among researchers, regardless of their disciplinary field.

Simultaneous pyometra and viable puppies’ gestation in a bitch Risso, Analia Lorena; Pellegrino, Francisco Javier; Corrada, Yanina Alejandra Here we describe a case of pyometra coexisting with gestation in a 4.5 year-old miniature short-haired Dachshund. The dog exhibited depression, vaginal discharge, polydipsia and dehydration. Ultrasound examination revealed the presence of low to moderate anechoic fluid collection in the left uterine horn. Blood analysis revealed mild neutrophilia with a left shift. Based on these findings a presumptive diagnosis of pyometra was made and the bitch was treated using amoxicillin-clavulanate with dopaminergic agonist (cabergoline). A second ultrasound scan revealed the presence of two gestational vesicles in the right uterine horn that were successfully carried to term. Unusually, while pyometra persisted in the left uterine horn, two viable puppies were delivered by caesarean section from the right uterine horn.

Amino acid metabolism conflicts with protein diversity Krick, Teresa Elena Genoveva; Verstraete, Nina; Alonso, Leonardo Gabriel; Shub, David A.; Ferreiro, Diego; Shub, Michael Ira; Sánchez Miguel, Ignacio Enrique The 20 protein-coding amino acids are found in proteomes with different relative abundances. The most abundant amino acid, leucine, is nearly an order of magnitude more prevalent than the least abundant amino acid, cysteine. Amino acid metabolic costs differ similarly, constraining their incorporation into proteins. On the other hand, a diverse set of protein sequences is necessary to build functional proteomes. Here, we present a simple model for a cost-diversity trade-off postulating that natural proteomes minimize amino acid metabolic flux while maximizing sequence entropy. The model explains the relative abundances of amino acids across a diverse set of proteomes. We found that the data are remarkably well explained when the cost function accounts for amino acid chemical decay. More than 100 organisms reach comparable solutions to the trade-off by different combinations of proteome cost and sequence diversity. Quantifying the interplay between proteome size and entropy shows that proteomes can get optimally large and diverse.

Hyphoderma romeroae sp. nov., a valid name for “Mutatoderma brunneocontextum” (Basidiomycota, Polyporales) Baltazar, Juliano M.; Rajchenberg, Mario Hyphoderma romeroae sp. nov. es propuesto para la especie “Mutatoderma brunneocontextum” C.E. Gómez que fuera inválidamente publicada previamente.; Hyphoderma romeroae sp. nov. is proposed for the species previously invalidly named as “Mutatoderma brunneocontextum” C.E. Gómez.

Numerical Simulations of Stick Percolation: Application to the Study of Structured Magnetorheological Elastomers Mietta, J. L.; Negri, Ricardo Martin; Tamborenea, Pablo Ignacio In this article we explore how structural parameters of composites filled with one-dimensional, electrically conducting elements (such as sticks, needles, chains, or rods) affect the percolation properties of the system. To this end, we perform Monte Carlo simulations of asymmetric two-dimensional stick systems with anisotropic alignments. We compute the percolation probability functions in the direction of preferential orientation of the percolating objects and in the orthogonal direction, as functions of the experimental structural parameters. Among these, we considered the average length of the sticks, the standard deviation of the length distribution, and the standard deviation of the angular distribution. We developed a computer algorithm capable of reproducing and verifying known theoretical results for isotropic networks and which allows us to go beyond and study anisotropic systems of experimental interest. Our research shows that the total electrical anisotropy, considered as a direct consequence of the percolation anisotropy, depends mainly on the standard deviation of the angular distribution and on the average length of the sticks. A conclusion of practical interest is that we find that there is a wide and well-defined range of values for the mentioned parameters for which it is possible to obtain reliable anisotropic percolation under relatively accessible experimental conditions when considering composites formed by dispersions of sticks, oriented in elastomeric matrices.

UV–Vis spectroscopic study and DFT calculation on the solvent effect of trimethoprim in neat solvents and aqueous mixtures Almandoz, M. C.; Sancho, Matias Israel; Duchowicz, Pablo Román; Blanco, Sonia Encarnacion The solvatochromic behavior of trimethoprim (TMP) was analyzed using UV–Vis spectroscopy and DFT methods in neat and binary aqueous solvent mixtures. The effects of solvent dipolarity/polarizability and solvent–solute hydrogen bonding interactions on the absorption maxima were evaluated by means of the linear solvation energy relationship concept of Kamlet and Taft. This analysis indicated that both interactions play an important role in the position of the absorption maxima in neat solvents. The simulated absorption spectra of TMP and TMP:(solvent)n complexes in ACN and H2O using TD-DFT methods were in agreement with the experimental ones. Binary aqueous mixtures containing as co-solvents DMSO, ACN and EtOH were studied. Preferential solvation was detected as a nonideal behavior of the wavenumber curve respective to the analytical mole fraction of co-solvent in all binary systems. TMP molecules were preferentially solvated by the organic solvent over the whole composition range. Index of preferential solvation, as well as the influence of solvent parameters were calculated as a function of solvent composition.

Cooperativity to increase Turing Pattern space for synthetic biology Diambra, Luis Anibal; Senthivel, Vivek Raj; Barcena Menendez, Diego; Isalan, Mark It is hard to bridge the gap between mathematical formulations and biological implementations of Turing patterns, yet this is necessary for both understanding and engineering these networks with synthetic biology approaches. Here, we model a reaction–diffusion system with two morphogens in a monostable regime, inspired by components that we recently described in a synthetic biology study in mammalian cells.1 The model employs a single promoter to express both the activator and inhibitor genes and produces Turing patterns over large regions of parameter space, using biologically interpretable Hill function reactions. We applied a stability analysis and identified rules for choosing biologically tunable parameter relationships to increase the likelihood of successful patterning. We show how to control Turing pattern sizes and time evolution by manipulating the values for production and degradation relationships. More importantly, our analysis predicts that steep dose–response functions arising from cooperativity are mandatory for Turing patterns. Greater steepness increases parameter space and even reduces the requirement for differential diffusion between activator and inhibitor. These results demonstrate some of the limitations of linear scenarios for reaction–diffusion systems and will help to guide projects to engineer synthetic Turing patterns.

Efecto de la precipitación sobre la dinámica hidrológica de las lagunas de la cuenca inferior del Río Colorado (período 1981-2011) Aliaga, Vanina Solange; Bohn, Vanesa Yael; Piccolo, Maria Cintia; Perillo, Gerardo Miguel E. The purpose of this study was to analyze the temporal dynamics of shallow lakes during the 2002-2012 years in the Colorado River Basin in relation to climate variability. Dry and humid periods were identified by water balance. Moreover, the influence of the extreme rainfall events on the shallow lakes in the region was analyzed. Shallow lakes area was estimated during three different years by satellite image processing (LANDSAT 5TM y 7 ETM). Water bodies were classified according to geomorphological, hydrological and morphometric criteria during a normal period. According rainfall amounts, 2011, 2004 and 2008 were considered normal, wet and dry years, respectively. As a result, 15 (normal), 20 (wet), and 5 (dry) shallow lakes which covered an area of 13.05, 14.54, and 5.8 km2 respectively were detected. A correlation between the area covered by water and the annual precipitation was obtained in the study area. As a result of the clustering method application, 3 groups of water bodies were defined. The first included the biggest and permanent water bodies (area > 1.5 km2). Group 2 included salt shallow lakes which Total Maximum Length (TML) orientation was N-S. The remaining group was composed by lakes located in the wettest area of the basin with an E-W LMT orientation.